350x woes...plug results**videos**

[longbedGTs]

Ever since I took my 350x for a ride since a months storage, its been cutting out intermittantly. Ive tried cleaning the carb and even installed new jets. Ive played with the needle clip positions all to no avail. I got a new spark plug and still no dice. I cant get my camera to focus up close, but the porcelin part looks a very light brown and the electrode looks almost white. Now Im pretty sure thats lean, right? Ive tried everything to richen it up and nothing works. Any ideas? Air leak possibly? Ive tried the WD40 trick and the engine speed didnt increase.
It has great power when you feel that sudden burst of it running right, then it falls on its face. I still havent adjusted the valves yet...

Ive got a few videos of it running poorly, so while the others are uploading, here is the first. Note in the first video when I blip the throttle. Its like it shuts off until I release and rev it slowly. The last video is of it idling after the flog in the 2nd video. It will barely idle and almost shuts off a few times.

http://s131.photobucket.com/albums/p306/longbedGTs/?action=view&current=HPIM0615.flv

http://s131.photobucket.com/albums/p306/longbedGTs/?action=view&current=HPIM0616.flv

http://s131.photobucket.com/albums/p306/longbedGTs/?action=view&current=HPIM0617.flv

[DIGGER DOG]

It actually sounds as if its jetted perfect if the porcelean is brown I would have to see a pic( i know you cant get a good focus) check for intermittant spark ,check all electrical connections . does it idle? when you open it up to full throttle does it sound like a rev limiter is kicking in(I know there is no rev limiter on 350x) check for bad gas
and check to see if you have any air tubes clogged on carb somtimes mud dobbers
fill air tubes up with mud . you also might want to check the accelerator pump diaphraghm

[longbedGTs]

Yeah, it does act like it has a rev limiter. It idles really well and runs great at low RPMs. I have checked the 2 connections at the brain box near the airbox, but I havent checked for intermittant spark. Do you think the kill switch might be a culprit? Thanks, Ill check these things today. I wish I had some spare parts to try...

[money89tractors]

I could be WAY off here, but i know on my 250R while it was sitting a month and a half while the top end was being done, the CDI box somehow went bad. (ran perfect before the top end rebuild, then after the rebuild, it would cut out and only run for a few seconds)

Check all other possibilities before going this route, IE: spark plug wire and boot, coil, kill switch, and most of all, check the magnito . .. . it could very well be rusty.

-Phil

[longbedGTs]

You might be on to something 89. I removed and checked the 2 connections at the CDI box under the seat. They were fine so I plugged them back in. Ever since then, the trike is running much better although it still spits and sputters...just not as bad as before.

[DeePa]

definately sounds like an electrical problem to me

[i58829]

Sounds like you're getting close to figuring it out, i hope its nothing major. That's a clean and fairly low hour machine so i'm sure you can get it running like it should again...

[Erics350x]

It sounds like its running lean on the high speed circuit or running the bowl empty. Have tried cleaning the petcock and checking the gas cap to see if its venting? Was it setting in the weather without the fuel cap vent hose? That could let moisture in the fuel.

[sandpuppi101]

I had a similar problem on 2 350X's before,it idle'd fine and all the carb setting's were spot on.I was running the 05 carb's,and this happened after they had sat for a month or so.Sound's like the same symptom's.Here's what I did..I turned the gas on and took the cap off the tank,grabbed the hose off the lower bowl and the one on the side .I plugged off the one on the side with my finger and blew thru the one on the bottom of the bowl.Blow the fuel back into the tank,with both on and reserve.You will hear bubbling in the tank and eventually it will blow clear.You will have gas go backward's thru the system,and too the airbox,but it mite get ya up and running.Just my 2 cent's..

[Jonpin]

i had a similer problem i had ppl telling me my exaust might be pluged or something cause it would idle but if u tryed to rev it it just bogged down and it was making me very angry and then i tryed messing with it one day and to my horror there was some ugly top end noise so im like now i have real problems why me ,but i took the valve cover off and the whole adjuster and nut wher laying right there next to the valve so i was very happy that stuff did fall into the engine but i put it back together and adjusted and what do u know it runs good now WOOOOHOOOOO "it was the exaust valve" so the clogged exaust was kinda right but i didnt think it could have been clogged cause my pipe looks like swiss cheese but i have a cobra exaust commin in the mail so good luck with it

[Erics350x]

i had a similer problem i had ppl telling me my exaust might be pluged or something cause it would idle but if u tryed to rev it it just bogged down and it was making me very angry and then i tryed messing with it one day and to my horror there was some ugly top end noise so im like now i have real problems why me ,but i took the valve cover off and the whole adjuster and nut wher laying right there next to the valve so i was very happy that stuff did fall into the engine but i put it back together and adjusted and what do u know it runs good now WOOOOHOOOOO "it was the exaust valve" so the clogged exaust was kinda right but i didnt think it could have been clogged cause my pipe looks like swiss cheese but i have a cobra exaust commin in the mail so good luck with it
that usually cause poping when you rev it

[longbedGTs]

Update: I have the mixture screw out 2.5 turns and it runs great except for the intermittant sputtering. Im getting the frame painted, so the machine is tore down at the moment, but I did find something very interesting. At one of the two metal connections at the coil, there was one that had some little burn marks on it. Like...if something isnt quite making contact and you get a little arc and it makes a burn mark...kinda like when you connect the battery terminals on your car. Since I have everything tore down, I dont know if this is the culprit, but Im thinking it just may be.
I went over the connections at the coil before, but I guess I didnt look close enough. :rolleyes:

[Dammit!]

Random sputters like that are almost always electrical. Starving for fuel because the float bowl isn't filling up fast enough would normally be more consistent and the frequency of the sputters would increase as you gave it more throttle. Nothing in those vids sounded like a fuel problem to me.

If you had known about that burn mark before you tore it down you'd be able to look at in the dark while it's running. If it was arcing you'd be able to see it and tell if they sputters are coinciding with the sparks.

When you put it back together, put your jetting back to stock (put your airbox lid on if you don't normally run it) and get all your electrical issues sorted out. Then you can worry about fine tuning the jetting.